Frogging is not such a bad thing as it's cracked up to be. Sure, you've just spent months knitting and you would like there to be a finished product at the end of this tunnel. But wouldn't you rather it be a sweater you could be proud of instead of one you aren't really happy with?
If it were me, I'd start over. I have lots of things I made that I was really knocked out with and most of those are in a pile somewhere not being used.
Besides, knitting is a learning process. You may even find that your next attempt at knitting goes faster than your first because of all you learned while you were working on the sweater that didn't work out.
Best of luck with whatever you decide!